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jockhater2
04-23-2012, 04:29 PM
I was just at a local car audio show. Frost off in Madison, WI.

A guy showed up from IOWA. He had 6 18" SMDs. He did a 159. He had 3 DC 9ks.

He used to have a MTX Jackhammer 22. And did a 156.1

Is it that hard to gain decibels?

05trailblazer
04-23-2012, 04:31 PM
i bet it was over all louder with 6 18s but it is harder.

Ronny
04-23-2012, 04:31 PM
Yup. The louder you get, the tougher, and exponentially more equipment you need.

Ronny
04-23-2012, 04:34 PM
.... Or more concrete and steel tubing is needed... Lol :p

NutHugger
04-23-2012, 05:03 PM
I was just at a local car audio show. Frost off in Madison, WI.

A guy showed up from IOWA. He had 6 18" SMDs. He did a 159. He had 3 DC 9ks.

He used to have a MTX Jackhammer 22. And did a 156.1

Is it that hard to gain decibels?

I can't believe he did that number with a jackhammer. That number is pretty impressive for SMD's because they are not spl woofers. Anything over 150 takes some skill. 155's is above average skill. It is very difficult to gain. The equipment begins to matter much less than enclosure. You just need stuff that's going to hold together at those levels

wenn_du_weinst
04-23-2012, 05:13 PM
I can't believe he did that number with a jackhammer. That number is pretty impressive for SMD's because they are not spl woofers. Anything over 150 takes some skill. 155's is above average skill. It is very difficult to gain. The equipment begins to matter much less than enclosure. You just need stuff that's going to hold together at those levels

it's 6 18's

pr-festiva
04-23-2012, 05:15 PM
sounds like he did some thing very very right with the mtx

Phoenix Risen
04-23-2012, 05:24 PM
sounds like he did some thing very very right with the mtx

My thoughts exactly.

pr-festiva
04-23-2012, 05:38 PM
wonder if the meters and meter locations were the same

AVX Mike
04-23-2012, 05:42 PM
Yes, it is very hard to gain at a certain level. You start to fight yourself. As pressure on the front of the cone increases (spl number) it is that much harder to move the cone any farther. At a certain point you need to pay very close attention to the Bl of your woofers to make sure they can push against the pressure created in front of them. That's why Scott Owens topped out at 180 db with the pioneers. Not enough strength to fight the pressure.

I see you are also from WI. Stop by our shop in Brookfield if you're ever down this way. I used to compete a lot a few years ago, if you're looking to get into the scene or get louder I can help you out.

Kangaroux
04-23-2012, 05:45 PM
Is that the same guy with the really annoying voice who doesn't stop talking lol

TheUnderFighter
04-23-2012, 06:03 PM
I can't believe he did that number with a jackhammer. That number is pretty impressive for SMD's because they are not spl woofers. Anything over 150 takes some skill. 155's is above average skill. It is very difficult to gain. The equipment begins to matter much less than enclosure. You just need stuff that's going to hold together at those levels

I'll agree that's a pretty impressive number for the jackhammer....
but regardless of what woofers they are... he's got six 18s and 20kW+ of power, I'd expect a 159.

wenn_du_weinst
04-23-2012, 06:05 PM
does he have a red hummer?

mazdakid
04-23-2012, 06:45 PM
Said he didnt break 157 on caco w the 6 18s

NutHugger
04-23-2012, 07:33 PM
it's 6 18's

So? What if they were 18 inch pups or xplods if they had made 18's? Cone area is not nearly as important as reducing cancellation. More cones usually introduces more cancellation. What is wrong with the people on this forum? Everyone thinks they know, yet they have never done it, seen it done, and simply don't have a clue. Wenn do you ever know what you're talking about? Pun intended.

NutHugger
04-23-2012, 07:35 PM
I'll agree that's a pretty impressive number for the jackhammer....
but regardless of what woofers they are... he's got six 18s and 20kW+ of power, I'd expect a 159.

Cheesus Crust are you serious? Only a retard would think woofer + rated rms power at 1 ohm = magical number. No, you guys are idiots. What frequency is he tuned to? How is his box designed? What vehicle?

NutHugger
04-23-2012, 07:37 PM
The internet heros JP and Meade had 4 18's and what like 18kw. Neither of them could even touch a 154. I think they BOTH did 153 at 42hz IN THE KICK with the door wide open. We need one of those willy wonka pictures for you retards that says "oh so you know about car audio? Tell me all about how cone size and amp power = deebeez". idiots.

Edit: Sorry I was wrong meade did 157 at the dash http://www.youtube.com/watch?v=rjGt8UVveFg and 158 in the kick.

winkychevelle
04-23-2012, 07:39 PM
once u hit 155 its like hitting a brick wall gains are really hard to come by. you then need to get into coating resin on the box, moving the box, moving interior pieces, sitting on the truck, deadening and bracing it can get really hard.

and with that much power i bet power compression came into play where the coils heated up so much that their resistance got really high causing the amp to put out a very little bit

wenn_du_weinst
04-23-2012, 07:45 PM
The internet heros JP and Meade had 4 18's and what like 18kw. Neither of them could even touch a 154. I think they BOTH did 153 at 42hz IN THE KICK with the door wide open. We need one of those willy wonka pictures for you retards that says "oh so you know about car audio? Tell me all about how cone size and amp power = deebeez". idiots.

Edit: Sorry I was wrong meade did 157 at the dash Metering the Hoe&#39 (http://www.youtube.com/watch?v=rjGt8UVveFg) - TermLab SPL Numbers - 4 18" woofers 30,000 watt system - YouTube and 158 in the kick.

neither of those guys could design a box if their life depended it. There are guys doing 155's in the 30hz region with 2 15's... If you can't do high 150's with 6 18's your an idiot.

resonate
04-23-2012, 08:05 PM
neither of those guys could design a box if their life depended it. There are guys doing 155's in the 30hz region with 2 15's... If you can't do high 150's with 6 18's you're an idiot.

Fixed..

Continue bickering.

NutHugger
04-23-2012, 08:51 PM
neither of those guys could design a box if their life depended it. There are guys doing 155's in the 30hz region with 2 15's... If you can't do high 150's with 6 18's your an idiot.

You're not helping your case. More cone area does not = more spl. It just doesn't. It never has. Theoretically if you could apply infinite power to a woofer it would be ideal. Reducing cancellation is ultimately what SPL is about. NOT increasing cone area by way of adding more woofers. They introduce cancellation to each other. Next time you're at a show and someone has a wall you can get inside of, see if they will let you. Put your head in the center behind 2 or more woofers. however you can get in the center. Have them turn it up some. Notice the eery quiet of cancellation. Move a little and notice the crazy intense spl. that is because those woofers introduce cancellation to each other. We all know about the little tricks people can do to their interiors etc to gain BIG. How are those increasing rms power or cone area? I would bet you couldn't do high 50's if you have 6 18's. Why stop there. I bet you couldn't with 50 18's. See where this is going? By your logic if some is good more is better and it's clearly not.

05trailblazer
04-23-2012, 09:00 PM
can i hitz 160+ with some crunch equipment??

keep_hope_alive
04-23-2012, 09:12 PM
In addition, you start encountering losses in pressure through factory seals, A/C vents, even mid/midbass cones will move. I can play 12 Hz with subs only and watch my midbass cones move a lot in response to the pressure. You can see/feel the body panels giving. Flex is pressure loss. There is a reason why high SPL cars have thick Lexan windows, bolted doors, concrete, etc.

Multi sub builds suffer phase interference. You want to ensure that destructive interference does not occur at your peak frequency, but constructive interference does. Note also that mic location changes what frequencies are constructive/destructive.

A proper understanding and application of physics goes a long way.

chillin
04-23-2012, 10:16 PM
wenn_du_weinst and NutHugger

continue

:popcorn:

CHEMMINS
04-23-2012, 10:35 PM
You're not helping your case. More cone area does not = more spl. It just doesn't. It never has. Theoretically if you could apply infinite power to a woofer it would be ideal. Reducing cancellation is ultimately what SPL is about. NOT increasing cone area by way of adding more woofers. They introduce cancellation to each other. Next time you're at a show and someone has a wall you can get inside of, see if they will let you. Put your head in the center behind 2 or more woofers. however you can get in the center. Have them turn it up some. Notice the eery quiet of cancellation. Move a little and notice the crazy intense spl. that is because those woofers introduce cancellation to each other. We all know about the little tricks people can do to their interiors etc to gain BIG. How are those increasing rms power or cone area? I would bet you couldn't do high 50's if you have 6 18's. Why stop there. I bet you couldn't with 50 18's. See where this is going? By your logic if some is good more is better and it's clearly not.

If cone area didn't affect SPL, everyone would be running an 8" sub. Double the cone area, with all other things equal you should gain approximately 3 db. Give or take. Same as if you increase the given power by 2x.

chillin
04-23-2012, 10:47 PM
If cone area didn't affect SPL, everyone would be running an 8" sub. Double the cone area, with all other things equal you should gain approximately 3 db. Give or take. Same as if you increase the given power by 2x.

This. In a perfect world, 3db increase, but in real world there will be cancellation, however that's where knowing how to design comes into play. If done right, there wont be much cancellation.

I would like to see everyone burping with 8 inch subs with 4 inch vc's though.

NutHugger
04-23-2012, 10:53 PM
If cone area didn't affect SPL, everyone would be running an 8" sub. Double the cone area, with all other things equal you should gain approximately 3 db. Give or take. Same as if you increase the given power by 2x.

This is what I hate about people. Did I say that cone area COULD NOT affect spl? No, I said it does not automatically equal it. This is not me speaking out against cone area. This is me telling you it's not the end-all, be-all answer. I know it's hard for people to believe, but I'm not lying about it. Theoretically doubling cone area is +3db. There is no debating that. In reality it almost never happens. Same with doubling power. There will be forms of cancellation that mess that up for you, thus further proving my point. There are small woofers out there doing huge numbers. If cone area were required that would not be possible.

stl_314
04-23-2012, 11:05 PM
Ive seen 6 type r 12's do 155's on music in a blazer before

NutHugger
04-23-2012, 11:22 PM
Ive seen 6 type r 12's do 155's on music in a blazer before

Not calling bs, just hard for me to wrap my brain around.

CHEMMINS
04-23-2012, 11:35 PM
This is what I hate about people. Did I say that cone area COULD NOT affect spl? No, I said it does not automatically equal it. This is not me speaking out against cone area. This is me telling you it's not the end-all, be-all answer. I know it's hard for people to believe, but I'm not lying about it. Theoretically doubling cone area is +3db. There is no debating that. In reality it almost never happens. Same with doubling power. There will be forms of cancellation that mess that up for you, thus further proving my point. There are small woofers out there doing huge numbers. If cone area were required that would not be possible.

Well did you not state "More cone area does not = more spl"? Given all other system components are equal, with just a change in size of woofer......you will gain..... it is simple physics.

stl_314
04-23-2012, 11:38 PM
There is a couple people from st louis that can vouch for that...it was 2 sundown 3ks and walled off but I think it was tuned in the mid 40s

NutHugger
04-23-2012, 11:46 PM
Well did you not state "More cone area does not = more spl"? Given all other system components are equal, with just a change in size of woofer......you will gain..... it is simple physics.
Not necessarily. Not in all cases. You're just plain wrong. If you went from 2 18's in your suv to say 20 18's you're not going to gain. More IS NOT always louder. It's not just factual. What I've stated so far is absolutely true. if you're arguing it you've never broken a 150.

NutHugger
04-23-2012, 11:51 PM
I think the problem is you're not able to discern the difference between theoretical and reality.

keep_hope_alive
04-24-2012, 01:28 AM
i agree that simply adding cone area does not mean you will always gain in measured decibels - once you hit the threshold of what the vehicle can support. the system is dynamic - and non-linear at that point. many other variables come into play. besides, most people use shared airspace to save hassle/space which means excursion is reduced. so while you have more surface area, you have less excursion - could mean no gain or a reduction. above the threshold the subs fight themselves (as was already mentioned).

classical equations have a range of where they are applicable, and roll off outside of that range.

keep_hope_alive
04-24-2012, 01:38 AM
Competitor Stats: Nathan Munson (http://www.termpro.com/asp/competitorstats.asp?Competitor_ID=13416)

Competitor Stats: Nathan Munson (http://www.termpro.com/asp/competitorstats.asp?Competitor_ID=13416&Season=2012&Method=201)

I'll never forget the first time i read about Nate Munson breaking 170dB with a single 10" sub. That is a man who can understand and apply physics. And that was almost 10 years ago!

hispls
04-24-2012, 02:37 AM
Anybody else remember the days when all the top SPL scores were a dozen or more woofers? Alma Gates with 64 12's? I've seen enough of that style build to believe that if you stick enough best buy woofers in a van it'll get loud. After a point it becomes much more complicated, but I believe mid to high 50's is possible with almost anything in sufficient quantity.

winkychevelle
04-24-2012, 02:45 AM
Anybody else remember the days when all the top SPL scores were a dozen or more woofers? Alma Gates with 64 12's? I've seen enough of that style build to believe that if you stick enough best buy woofers in a van it'll get loud. After a point it becomes much more complicated, but I believe mid to high 50's is possible with almost anything in sufficient quantity.

i have to agree with a good design good power and a well sealed vehicle multi sub systems always get loud.

but i also believe it can only go up to a point at which the design fails and youve topped out

but with anything larger than 2 18s a person should be in the 155 range hitting anything higher is stupid hard and understandable to not reach but with that much cone area you have to break a 150

mlstrass
04-24-2012, 03:35 AM
I was just at a local car audio show. Frost off in Madison, WI.

A guy showed up from IOWA. He had 6 18" SMDs. He did a 159. He had 3 DC 9ks.

He used to have a MTX Jackhammer 22. And did a 156.1

Is it that hard to gain decibels?

what show were you at????? 6 18 SMD's and 3 DC9k's supposedly wired to .35ohm each, also had 4 DC alts. Serious set up for sure.

Did a 53.4 bass racing and might have broken a 55 on the dash with door open, don't remember exact score, but it wasn't loud for what he has. Peaked around 42-43Hz according to his Real SPL run.

He said he does a 57+ in the kick, but this wasn't a USACI show...

mlstrass
04-24-2012, 04:03 AM
Not necessarily. Not in all cases. You're just plain wrong. If you went from 2 18's in your suv to say 20 18's you're not going to gain. More IS NOT always louder. It's not just factual. What I've stated so far is absolutely true. if you're arguing it you've never broken a 150.

Why are you going to such extremes with your examples? Makes your arguement less valid IMO.

So are you saying that doubling cone area, assuming you have room to build a proper enclosure won't be louder 99% of the time?

I've broken a 50 once or twice...

subzero
04-24-2012, 07:00 AM
i was just at a local car audio show. Frost off in madison, wi.

A guy showed up from iowa. He had 6 18" smds. He did a 159. He had 3 dc 9ks.

He used to have a mtx jackhammer 22. And did a 156.1

is it that hard to gain decibels?
yes

NutHugger
04-24-2012, 07:38 AM
Why are you going to such extremes with your examples? Makes your arguement less valid IMO.

So are you saying that doubling cone area, assuming you have room to build a proper enclosure won't be louder 99% of the time?

I've broken a 50 once or twice...
No and No. How can you miss the point of my examples? These guys have said that adding cone area and power is what is required to create spl and threw out enclosure design altogether. So I have used absurdity to demonstrate their absurd opinions. I even keep saying "by your logic if some is good then more is better right?". So how could you miss the point? I suppose we should talk about your lack of comprehension, or your self proclaimed credibility. I've broken 150 a few times too. Before just now had I said that? Was it necessary to try to boost my e-peen? Nah. It wasn't. I'm just trying to straighten out a few misguided people in here. I'm obviously correct so I'm not really sure why you or anyone else who says they know what they are talking about would want to argue.

Why So Cereal?
04-24-2012, 12:14 PM
I'm obviously correct so I'm not really sure why you or anyone else who says they know what they are talking about would want to argue.

How's the weather up there?

NutHugger
04-24-2012, 12:18 PM
How's the weather up there?

Really? People want to take shots because I know I'm right about something?... especially something as known as just adding a bunch of woofers is not going to help with SPL. You act like people should just bumble through life never sure of anything.

jockhater2
04-24-2012, 05:23 PM
ok. So I got some info for you guys.

His vehicle is a tahoe. It looks like a daily ground pounder. He was a really cool guy and very nice. It was not a wall. And the boxs port was tuned to 34hertz. and he said there wasnt enough port for the 6 subs.

Also. The reason at the show he only hit 157 is because 1 or 2 of the DC 9ks went into project. I didn't catch the full announcement on that. Just that he pulled off to the size to fix his amp.

A new camera... and a 158 on music - YouTube (http://www.youtube.com/watch?v=Op6hTByZrCw)


and the Jackhammer was on like 12k or something and it was in the back of the tahoe.

skip to 8 minutes. thats where it shows 156.1

MTX Jackhammer in my 01&#39 (http://www.youtube.com/watch?v=zsfJJzH_8IY) Tahoe - YouTube

chillin
04-24-2012, 05:41 PM
neither of those guys could design a box if their life depended it. There are guys doing 155's in the 30hz region with 2 15's... If you can't do high 150's with 6 18's your an idiot.


No and No. How can you miss the point of my examples? These guys have said that adding cone area and power is what is required to create spl and threw out enclosure design altogether. So I have used absurdity to demonstrate their absurd opinions. I even keep saying "by your logic if some is good then more is better right?". So how could you miss the point? I suppose we should talk about your lack of comprehension, or your self proclaimed credibility. I've broken 150 a few times too. Before just now had I said that? Was it necessary to try to boost my e-peen? Nah. It wasn't. I'm just trying to straighten out a few misguided people in here. I'm obviously correct so I'm not really sure why you or anyone else who says they know what they are talking about would want to argue.

By saying neither of those guys could design a box, I would think that implies adding more woofers is based on knowing how to build a proper enclosure. I wouldn't say he threw out the idea of enclosure design.

bhsdriller
04-24-2012, 06:03 PM
supposedly this guys going to a wall....designed properly should be a 60+

keep_hope_alive
04-24-2012, 06:06 PM
supposedly this guys going to a wall....designed properly should be a 60+


assuming the vehicle is capable of achieveing that. enclosure aside - the SPL jump between classes up to Extreme has less to do with equipment and more to do with vehicle reinforcement/seals. correct? obviously, the enclosure is key. but move the enclosure into different vehicles and you'll get different results.

bhsdriller
04-24-2012, 06:11 PM
assuming the vehicle is capable of achieveing that. enclosure aside - the SPL jump between classes up to Extreme has less to do with equipment and more to do with vehicle reinforcement/seals. correct? obviously, the enclosure is key. but move the enclosure into different vehicles and you'll get different results.

true...those guys put tons and tons of work into their cars to get as less flex/vibration as possible. They also put just as much into the box
The equipment will be capable of doing a high #, but the vehicle could hold him back

keep_hope_alive
04-24-2012, 06:28 PM
if/when i do a dedicated SPL vehicle - i'll probably start with something from the 50's when steel was thick and hammer-proof and the vehicle was simple, dashes were metal, etc. it'll be a single sub. like a 50's wagon or pickup with a blow-through. i think people make a lot more work for themselves by using modern vehicles with metal so thin you can flex it with your hand. further, older vehicles had more curves - curves are stronger than flat expanses.

wenn_du_weinst
04-24-2012, 06:35 PM
I think nutthugger = ecrack.net's brother.

R34P3R
04-24-2012, 06:49 PM
I think nutthugger = ecrack.net's brother.

He seems very butthurt about this subject for some reason. I'm not even sure why this argument is occurring?

jockhater2
04-24-2012, 08:41 PM
if/when i do a dedicated SPL vehicle - i'll probably start with something from the 50's when steel was thick and hammer-proof and the vehicle was simple, dashes were metal, etc. it'll be a single sub. like a 50's wagon or pickup with a blow-through. i think people make a lot more work for themselves by using modern vehicles with metal so thin you can flex it with your hand. further, older vehicles had more curves - curves are stronger than flat expanses.

make a body of carbon fiber.

keep_hope_alive
04-24-2012, 08:45 PM
make a body of carbon fiber.

i like the idea, but not the effort. :) i am ok with an SPL vehicle weighting 7,000 pounds. :)

cyn
04-24-2012, 08:52 PM
okay while on this subject lol... whats the loudest trunk setup to date with the rear seat up and not down with no blow through to the inside cabin?

mlstrass
04-25-2012, 03:42 AM
window height/angle and depth of dash also play a big part on how a vehicle meters sealed up.

My van has a big *** windshield and very deep dash, that's why serious SPL competitors use other versions. I don't chase numbers so it's all good.

The Hoe is a "walled" vehicle per dBdrag rules since he's several inches above windowline, but yes it's not a true walled vehicle.

He and I got off to a bad start, but I still respect him for coming out and demoing/competing.

VisceralSound
04-25-2012, 03:48 AM
okay while on this subject lol... whats the loudest trunk setup to date with the rear seat up and not down with no blow through to the inside cabin?

That would be a fun number to chase for haha.